The inertia cone crushers now in use comprise a crushing bowl accommodating a breaking head therein to form an annular crushing space therebetween. The breaking head is installed on a spherical support fastened to the crusher shell like the crushing bowl. The shaft of the breaking head is arranged within a bearing bush carrying an out-of-balance weight on its outer surface. The bush is linked with a drive arranged in the lower portion of the crusher by means of a flexible transmission.
The installation height of inertia crushers is determined by the length of the flexible transmission which is the principal assembly of the crusher defining the complexity of its construction, the labor input in service and the cost of construction of the structures used to install the crusher.
During the crusher operation the liner mounted on the crusher breaking head is worn and requires replacement. Due to the construction features of the crusher the breaking head must be removed at the repair site in order to replace the liner. This operation in conjunction with further re-installation of the breaking head into the crusher is complicated by the flexible coupling of the bush with the drive and the necessity to fix the bush in a position as close as possible coaxially with the crusher shell.
Known in the prior art is an inertia cone crusher (cf. USSR Author's Certificate No. 596 280,) comprising a shell installed through elastic shock-absorbers on a base and having a crushing bowl, a breaking head with a shaft mounted on a spherical support made in the shell, an out-of-balance unit made as a bearing bush provided with an out-of-balance weight, installed on the shaft of the breaking head and connected by means of a flexible transmission with a drive rigidly fixed on the base.
In this construction the flexible transmission is made as a ball spindle being both a driving member and a support for the out-of-balance unit. The spherical tips of the spindle are provided with sockets having balls installed therein and are arranged in slit bores of the bearing bush and of the drive.
The articulated joints of the transmissions used do not provide the vertical position of the bush when the breaking head is dismantled, therefore before its dismantling the bush is placed coaxially with the shell axis by means of saddles placed under the out-of-balance weight which are removed from the crusher after the breaking head is reinstalled. This operation is time and labor-consuming. The spindle and the slots for the tips thereof are complex and require a high degree of accuracy in their manufacture, making the construction of the machine as a whole more expensive.
The operation of the spindle as a driving member and a support for the out-of-balance unit reduces its life and the reliability of the drive to which the axial load is transmitted.
Furthermore, connection of the out-of-balance unit with the drive by a single spindle increases the height of installation since it is necessary to organize a complicated oil and dust sealing between the movable shell and its base.
Also known in the prior art is an inertia cone crusher (cf. USSR Author's Certificate No. 632 388,) comprising a shell installed through elastic shock-absorbers on a base and having a crushing bowl, a breaking head with a shaft mounted on a spherical support made in the shell, an out-of-balance unit made as a bearing bush provided with an out-of-balance weight, installed on the shaft of the breaking head and linked by means of a flexible transmission with a drive rigidly fixed on the base.
In this crusher the flexible transmission is made as a ball spindle connecting the bearing bush with an intermediate shaft journaled in shell bearings and linked by its lower end with the drive by means of a second ball spindle or an elastic compensation clutch.
Like in the previous analogue, the upper ball spindle serves to function both as a driving member and a support for the out-of-balance unit; however, here it transfers the axial load through the bearings of the intermediate shaft to the shell. This increases the life of the drive, but complicates the construction and increases the production cost of the machine since new additional members--the intermediate shaft with bearings and the additional spindle or the clutch--are introduced into the transission.
The members introduced additionally into the transmission increase still more the installation height of the crusher as compared with the previous crusher and do not simplify the dismantling and re-installation of the breaking head.
Also known is an inertia cone crusher (cf. USSR Author's Certificate No. 419 240).
This crusher comprises a shell installed through elastic shock-absorbers on a base and having a crushing cone, a breaking head with a shaft mounted on a spherical support made in the shell, an out-of-balance unit made as a bearing bush installed on the breaking head shaft and provided with an out-of-balance weight and a carrier disc, a rod used for mounting said out-of-balance unit on the breaking head and having its lower end mounted in the bearing bush, and a means for mounting the upper end of the rod in an upper portion of the breaking head.
As distinguished from the previous constructions, mounting of the out-of-balance unit in this crusher on the breaking head allows to the elimination of the axial load acting on the flexible transmission and driving member. This improves the reliability of the transmission. However, since the upper end of the rod is fastened to the upper portion of the breaking head, the dismantling of the latter is substantially complicated by the fact that it is first necessary to disassemble its liner fastening in order to provide access to the rod fastening assembly. This is a very labor-consuming operation, especially for industrial large-size crushers. Large crusher installation height, complexity of the construction and the labor-consuming operations for the breaking head liner replacement involve the same difficulties as in the previously discussed crushers.